This invention relates to novel hydroxamic acid compounds which are useful as pharmaceuticals, e.g., in inhibiting matrix metalloproteinases such as collagenase, and in inhibiting TNF production, particularly for treatment of diseases or conditions mediated by over-production of or over-responsiveness to TNFxcex1.
Tumor necrosis factor (TNF) is a cytokine which is produced initially as a membrane-bound 28 kD precursor. It is then cleaved by an enzyme (TNF convertase) and released as a soluble, active 17 kD form. Soluble TNF exists in at least two forms, TNFxcex1 and TNFxcex2, of which TNFxcex1 appears to be the more significant clinically. TNFxcex1 is believed to mediate inflammation and other conditions associated with septic shock or acute infections. Long term overstimulation by TNFxcex1 is believed to play a role in autoimmune and chronic inflammatory conditions, such as arthritis, multiple sclerosis, and the like.
It has been shown that certain matrix metalloproteinase inhibitors of the hydroxamic acid class, in particular 3-imino-4-oxo-heptane-1,7-dioic acid (7-N-hydroxy) diamides (which are optionally further 1-N-, 2-, 5-, and 6-substituted) are capable of mediating TFNxcex1 production, possibly by inhibiting TNF convertase. Known representatives of this class of compounds are summarized and described, e.g., in WO 94/10990.
It has now surprisingly been discovered that a new class of hydroxamic acid derivatives (xe2x80x9cNovel Compoundsxe2x80x9d) are potent TNFxcex1 suppressors and have advantageous pharmaceutical properties, in particular, oral bioavailability.
The Novel Compounds are 3-imino-4-oxo-6-(oxymethyl)-heptane-1,7-dioic acid (7-N-hydroxy) diamides. Suitably, the 6-oxymethyl substituent is of formula II below, e.g., hydroxymethyl or mono- or polyalkoxymethyl. The Novel Compounds may have further substitutions at the 1-N-, 2-, and 5-positions as known in the art, e.g., as described in WO 94/10990, or as further described herein. For example, the Novel Compounds may be 1-N substituted with methyl, pyridyl, or a substituent of formula Xxe2x80x94Yxe2x80x94 or Xxe2x80x2xe2x80x94Yxe2x80x94 as described below, e.g., 3-imino-4-oxo-6-(oxymethyl)-heptane-1,7-dioic acid (1-N-morpholinocarbonylalkyl, 7-N-hydroxy) diamide, and may be in free or pharmaceutically acceptable salt form.
A particularly preferred class of Novel Compounds are 3-imino-4-oxo-5-aryl-6-(oxymethyl)-heptane-1,7-dioic acid (7-N-hydroxy) diamides. The 5-aryl substituent may be as further described herein, e.g. wherein the 5-aryl substituent is phenyl optionally substituted, conveniently at the 4-position, e.g. by hydroxy-, C1-6 alkyl-, C1-6 alkoxy-, amino-, halo- or cyano-. Such 5-aryl substituted Novel Compounds may be in free or pharmaceutically acceptable salt form.
Preferably, the Novel Compounds are of Formula I 
wherein
R1 is a substituent of Formula II:
Axe2x80x94(Oxe2x80x94(CR5H)n)mxe2x80x94Oxe2x80x94CH2xe2x80x94xe2x80x83xe2x80x83Formula II
xe2x80x83wherein
n is 1, 2, 3 or 4, preferably 2;
m is 0, 1, 2 or 3;
each R5 is
independently H, C1-6 (optionally hydroxy-, C1-6 alkoxy-, amino-, C1-6 alkylamino-, thiol-, C1-6 alkylmercapto- or protected hydroxy, amino or thiol substituted) alkyl, C2-6 alkenyl, C6-14(optionally hydroxy-, C1-6 alkoxy-, amino-, C1-6 alkylamino-, halo- or cyano- substituted) aryl, or C6-14 (aryl) C1-6 alkyl; preferably H, phenyl, benzyl or C1-5 alkyl;
A is hydrogen, C1-10 alkyl, C6-14 aryl, C6-14 aryl, (C1-6 alkyl), (C6-14 aryl)carbonyl, or (C1-10 alkyl)carbonyl; preferably hydrogen, C1-6 alkyl (e.g., methyl or cyclohexyl), phenyl or benzyl;
R2 is C2-12 alkyl, C3-12 alkenyl, C3-7(optionally hydroxy-, C1-6 alkoxy-, amino-, or C1-6 alkylamino- substituted) cycloalkyl, C5-14 aryl, or C5-14 aryl(C1-6 alkyl), wherein aryl groups are optionally substituted by hydroxy-, C1-6 alkyl-, C1-6 alkoxy-, amino-, halo- or cyano-; preferably phenyl, 4-methylphenyl, 4-methoxyphenyl, cyclohexyl or isobutyl;
R3 is C1-10 (optionally hydroxy- or C1-6 alkoxy- amino-, C1-6 alkylamino-, thiol-, C1-6 alkylmercapto- or protected hydroxy-, amino- or thiol- substituted) alkyl (e.g., t-butyl, or cyclohexylmethyl), C6-14 (optionally hydroxy-, C6-14 aryloxy-, or C1-6 alkoxy-, amino-, C1-6 alkylamino-, halo-, or cyano- substituted) aryl (e.g., benzyl, p-methoxybenzyl, p-benzyloxybenzyl), or indolylmethyl (e.g., 2-indolylmethyl); preferably benzyl or t-butyl;
R4 is methyl, pyridyl, or a substituent of formula Xxe2x80x94Yxe2x80x94 wherein X is morpholino, pyridyl or aryl (preferably morpholino), and Y is C1-12 alkylene in which up to four of the methylene (xe2x80x94CH2xe2x80x94) units are optionally replaced with xe2x80x94COxe2x80x94, xe2x80x94NHxe2x80x94, xe2x80x94SO2xe2x80x94 or xe2x80x94Oxe2x80x94; for example methyl, 2-pyridyl, morpholinocarbonylmethyl, 5-morpholino)pentyl, or 5-(morpholinocarbonyl)pentyl.
xe2x80x9calkylxe2x80x9d includes linear, cyclic, or branched alkyl; and
xe2x80x9carylxe2x80x9d refers to an monovalent aromatic radical containing one or two aromatic rings, e.g., phenyl, benzyl, or tolyl, and includes heteroaryl containing one or more hetero atoms, e.g. N, O or S.
Halo or halogen as used herein refers to F, Cl, Br or I unless otherwise indicated.
Conveniently R1 is a substituent of formula IIxe2x80x2
Axe2x80x94(Oxe2x80x94(CH2)n)mxe2x80x94Oxe2x80x94CH2xe2x80x94xe2x80x83xe2x80x83Formula IIxe2x80x2
wherein A, n and m are as defined above.
In an alternative particular embodiment R1 is a substituent of formula IIxe2x80x3
Axe2x80x94Oxe2x80x94(CHR5xe2x80x94(CH2)n)mxe2x80x2xe2x80x94Oxe2x80x94CH2xe2x80x94xe2x80x83xe2x80x83Formula IIxe2x80x3
wherein A, n and R5 are as defined above and mxe2x80x2 is 0, 1 or 2.
When R4 of formula I is a substituent of formula Xxe2x80x94Yxe2x80x94, it is preferably a substituent of formula Xxe2x80x2xe2x80x94Yxe2x80x94 wherein Xxe2x80x2 is morpholino and Y is as defined above.
In particular embodiments the invention provides Novel Compounds of formula I in which independently:
n of Formula II is 3 or 4; or
R5 of Formula II is not H; or
R2 is C7-12 alkyl, C3-12 alkenyl, C3-7(optionally hydroxy-, C1-6 alkoxy-, amino-, or C1-6 alkylamino- substituted) cycloalkyl, C5-14 aryl, or C5-14 aryl(C1-6 alkyl), wherein aryl groups are optionally substituted by hydroxy-, C1-6 alkyl-, C1-6 alkoxy-, amino-, halo- or cyano-; preferably phenyl, 4-methylphenyl, 4-methoxyphenyl or cyclohexyl; or R3 is C1-10(amino-, C1-6 alkylamino-, thiol-, C1-6 alkylmercapto- or protected hydroxy-, amino- or thiol- substituted)alkyl, C6-14(amino-, C1-6 alkylamino-, halo-, or cyano- substituted)aryl; or
any aryl group thereof is heteroaryl containing one or more hetero atoms, e.g. N, O or S.
In further particular embodiments the invention provides Novel Compounds of formula Ixe2x80x2 
in which
R1xe2x80x2 is a substituent of Formula IIxe2x80x2xe2x80x3:
Axe2x80x2xe2x80x94(Oxe2x80x94(CH2)nxe2x80x2)mxe2x80x2xe2x80x94Oxe2x80x94CH2xe2x80x94xe2x80x83xe2x80x83Formula IIxe2x80x2xe2x80x3
xe2x80x83such that
nxe2x80x2 is an integer one or two, preferably two;
mxe2x80x2 is an integer zero, one, two, or three;
Axe2x80x2 is hydrogen, C6-14 aryl, C1-10 alkyl, (C6-14 aryl)carbonyl, or (C1-10 alkyl)carbonyl, (preferably C1-6 alkyl, e.g., methyl or cyclohexyl);
R2xe2x80x2 is C2-6 alkyl, preferably isobutyl;
R3xe2x80x2 is C1-10 (optionally hydroxy- or C1-6 alkoxy-substituted) alkyl (e.g., t-butyl, or cyclohexylmethyl), C6-14 (optionally hydroxy-, C6-14 aryloxy-, or C1-6 alkoxy-substituted) aryl (e.g., benzyl, p-methoxybenzyl, p-benzyloxybenzyl), or indolylmethyl (e.g., 2-indolylmethyl); preferably benzyl or t-butyl;
R4xe2x80x2 is methyl, pyridyl, or a substituent of formula Xxe2x80x94Yxe2x80x94 wherein X is morpholino, pyridyl or aryl (preferably morpholino), and Y is C1-12 alkylene in which up to four of the methylene (xe2x80x94CH2xe2x80x94) units are optionally replaced with xe2x80x94COxe2x80x94, xe2x80x94NHxe2x80x94, xe2x80x94SO2xe2x80x94 or xe2x80x94Oxe2x80x94; for example methyl, 2-pyridyl, morpholinocarbonylmethyl, 5-(morpholino)pentyl, or 5-(morpholinocarbonyl)pentyl;
Preferred Novel Compounds in which R2 is aryl are compounds in which R1 is of formula IIxe2x80x2 as defined above and R2 is phenyl, 4-methylphenyl or 4-methoxyphenyl.
An especially preferred group of compounds of Formula I are compounds wherein:
(i) R1 is of formula IIxe2x80x2 or IIxe2x80x3 (preferably formula IIxe2x80x2) and A of formula II is hydrogen, C1-6 alkyl, e.g., methyl or cyclohexyl (e.g., so that R1 of formula I is for example hydroxymethyl, cyclohexyloxyethoxymethyl, methoxyethoxyethoxymethyl, or hydroxyethyloxymethyl) or (C6-14 aryl)carbonyl, e.g. benzoyl (e.g. so that R1 of formula I is for example benzoyloxymethyl, benzoyloxyethoxyethyl or benzoyloxyethoxyethoxymethyl);
(ii) R2 of formula I is cyclohexyl, phenyl, 4-methylphenyl, 4-methoxyphenyl or isobutyl;
(iii) R3 of formula I is benzyl or t-butyl; and
(iv) R4 of formula I is methyl or morpholinocarbonyl(C1-6)alkyl.
The Novel Compounds may exist in free or salt forms, and salt forms are intended to be encompassed by the scope of the invention. For example, certain of the Novel Compounds may exist as physiologically acceptable acid or base addition salts, e.g. as chlorhydrates, oxalates or fumarates.
The configuration of the Novel Compounds is preferably that of Formula Ia: 
or of Formula Ib: 
most preferably that of Formula Ia.
Thus the invention includes Novel Compounds when in the form of mixtures of enantiomers, e.g. as racemic mixtures, though preferably when in pure or substantially pure enantiomeric form, e.g. in a form in which the Novel Compound content comprises at least 90%, preferably at least 95%, and especially at least 98%, of a single isomer (i.e. comprises less than 10%, preferably less than 5%, and especially less than 2%, of other Novel Compound isomers.
In further aspects, the invention provides novel processes for the preparation of a compound of formula I or an intermediate of formulae III, IV, or V below, comprising:
a) for preparation of a compound of formula I as defined above, reacting a compound of Formula III: 
xe2x80x83wherein R1, R2, R3 and R4 are as defined above, with hydroxylamine (optionally in salt or Oxe2x80x94 substituted form, e.g., hydroxylamine hydrochloride), recovering the product of formula I, and optionally deprotecting the product or separating the desired diastereoisomer if required;
b) for preparation of a compound of Formula III as defined above, oxidizing the olefin bond of a compound of formula IV: 
xe2x80x83wherein R1, R2, R3 and R4 are as defined above, e.g., using an oxidation catalyst such as ruthenium(III)chloride hydrate, to obtain the acid of Formula III, and optionally separating the desired diastereoisomer if required;
c) for preparation of a compound of formula IV, reacting a carboxylic acid of formula V
CH2xe2x95x90CHxe2x80x94CH(R1)xe2x80x94CH(R2)xe2x80x94COOHxe2x80x83xe2x80x83Formula V
xe2x80x83wherein R1 and R2 are as defined above, with an amino acid amide of formula VI
NH2xe2x80x94CH(R3)xe2x80x94COxe2x80x94NHR4)xe2x80x83xe2x80x83Formula VI
xe2x80x83wherein R3 and R4 are as defined above, to yield an amide corresponding to formula IV, and optionally separating the desired diastereoisorner if required, and
d) for preparation of a compound of formula V, reacting an alcohol of formula IIIV
xe2x80x83Axe2x80x3xe2x80x94(Oxe2x80x94(CR5H)n)mxe2x80x94OHxe2x80x83xe2x80x83Formula IIIV
wherein Axe2x80x3 is as defined above for A of formula II, except that when A is H, Axe2x80x3 is an O-protecting group (for example a group capable of forming a readily cleavable ether, e.g., benzyl), and wherein R5, n and m are as defined for Formula II above, with a dihalogenated alkene (trans), e.g., 1,4-dibromobut-2-ene, to obtain the disubstituted R1, halo-alkene, e.g., R1xe2x80x94CHxe2x95x90CHxe2x80x94CH2xe2x80x94W (trans), where W is halogen, e.g., bromine, which is then reacted with a carboxylic acid corresponding to R2, i.e. R2xe2x80x94CH2COOH, to yield the ester, which is then rearranged, e.g., in the presence of an organic base such as lithium diisopropyl amide, to give the compound of formula V.
Optionally, protecting and deprotecting steps may be included in the above described processes as necessary to preserve the integrity of the intermediates and the final product.
The invention further includes per se the novel intermediates of formulae III and IV as defined above.
As discussed in the test examples below, the Novel Compounds are potent inhibitors of TNFxcex1 release, are orally active, and are not cytotoxic at their effective doses. The Novel Compounds also inhibit collagenase and stromelysin at concentrations of from 0.3 to 10 nM. The Novel Compounds tested further show oral activity in vivo at dosages of less than 10 mg/kg in LPS induced TNFxcex1 release in the rat, and appear to be well tolerated at such dosages. Accordingly, the Novel Compounds have pharmaceutical utility as follows:
The Novel Compounds are useful for the prophylaxis and treatment of diseases or pathological conditions mediated by TNF, especially TNFxcex1, e.g., inflammatory conditions, autoimmune diseases, severe infections, and organ or tissue transplant rejection, e.g. for the treatment of recipients of heart, lung, combined heart-lung, liver, kidney, pancreatic, skin or corneal transplants and for the prevention of graft-versus-host disease, such as following bone marrow transplants.
The Novel Compounds are particularly useful for the treatment, prevention, or amelioration of autoimmune disease and of inflammatory conditions, in particular inflammatory conditions with an aetiology including an autoimmune component such as arthritis (for example rheumatoid arthritis, arthritis chronica progrediente and arthritis deformans) and rheumatic diseases. Specific auto-immune diseases for which the Novel Compounds may be employed include autoimmune haematological disorders (including e.g. hemolytic anaemia, aplastic anaemia, pure red cell anaemia and idiopathic thrombocytopenia), systemic lupus erythematosus, polychondritis, sclerodoma, Wegener granulamatosis, dermatomyositis, chronic active hepatitis, myasthenia gravis, psoriasis, Steven-Johnson syndrome, idiopathic sprue, autoimmune inflammatory bowel disease (including e.g. ulcerative colitis and Crohn""s disease), endocrine ophthalmopathy, Graves disease, sarcoidosis, multiple sclerosis, primary biliary cirrhosis, juvenile diabetes (diabetes mellitus type I), uveitis (anterior and posterior), keratoconjunctivitis sicca and vernal keratoconjunctivitis, interstitial lung fibrosis, psoriatic arthritis and glomerulonephritis (with and without nephrotic syndrome, e.g. including idiopathic nephrotic syndrome or minimal change nephropathy).
The Novel Compounds are also useful for the treatment, prevention, or amelioration of asthma, bronchitis, pneumoconiosis, pulmonary emphysema, and other obstructive or inflammatory diseases of the airways.
The Novel Compounds are useful for treating undesirable acute and hyperacute inflammatory reactions which are mediated by TNF, especially by TNFxcex1, e.g., acute infections, for example septic shock (e.g., endotoxic shock and adult respiratory distress syndrome), meningitis, pneumonia; and severe burns; and for the treatment of cachexia or wasting syndrome associated with morbid TNF release, consequent to infection, cancer, or organ dysfunction, especially AIDS -related cachexia, e.g., associated with or consequential to HIV infection.
In addition to inhibiting the release of TNF, especially TNFxcex1 through the suppression of TNF convertase, the Novel Compounds are also inhibitors of matrix metalloproteinases, e.g., collagenase, stromelysin and gelatinases, and hence useful for the indications known for collagenase inhibitors or other matrix metalloproteinase inhibitors, e.g., treatment of various pathological conditions of the skin, bones, and connective tissues, e.g., rheumatoid arthritis, psoriasis, psoriatic arthritis, osteoporosis, osteoarthritis, periodontitis, gingivitis, and corneal ulceration; for the treatment of cardiovascular disease, e.g., atherosclerosis, and coronary angioplasty; for the prevention of tumor cell metastasis and invasion and in inducing fibrosis of tumors, e.g., in the treatment of cancer; and for the prevention of neurodegenerative disorders, e.g., Alzheimer""s disease.
For the above indications the appropriate dosage will, of course, vary depending, for example, on the particular Novel Compound employed, the subject to be treated, the mode of administration and the nature and severity of the condition being treated. However, in general, satisfactory results in animals are obtained at daily dosages of from about 1 to about 10 mg/kg/day p.o. In larger mammals, for example humans, an indicated daily dosage is in the range of from about 50 to about 750 mg of Novel Compound administered orally once or, more suitably, in divided dosages two to four times/day.
The Novel Compounds may be administered by any conventional route, e.g. orally, for example in the form of solutions for drinking, tablets or capsules or parenterally, for example in the form of injectable solutions or suspensions. Normally for systemic administration oral dosage forms are preferred, although for some indications the Novel Compounds may also be administered topically or dermally, e.g. in the form of a dermal cream or gel or like preparation or, for the purposes of application to the eye, in the form of an ocular cream, gel or eye-drop preparation; or may be administered by inhalation, e.g., for treating asthma. Suitable unit dosage forms for oral administration comprise e.g. from 25 to 250 mg Novel Compound per unit dosage.
In accordance with the foregoing the present invention also provides in a further series of embodiments:
A. A method of inhibiting production of soluble TNF, especially TNFxcex1, or of reducing inflammation in a subject (i.e., a mammal, especially a human) in need of such treatment which method comprises administering to said subject an effective amount of a Novel Compound, or a method of treating any of the above mentioned conditions, particularly a method of treating an inflammatory or autoimmune disease or condition, e.g., multiple sclerosis or rheumatoid arthritis, or alleviating one or more symptoms of any of the above mentioned conditions.
B. A Novel Compound for use as a pharmaceutical, e.g. for use as an immunosuppressant or antiinflammatory agent or for use in the prevention, amelioration or treatment of any disease or condition as described above, e.g., an autoimmune or inflammatory disease or condition.
C. A pharmaceutical composition comprising a Novel Compound in association with a pharmaceutically acceptable diluent or carrier, e.g., for use as an immunosuppressant or antiinflammatory agent or for use in the prevention, amelioration or treatment of any disease or condition as described above, e.g., an autoimmune or inflammatory disease or condition.
D. Use of a Novel Compound in the manufacture of a medicament for use as an immunosuppressant or anti-inflammatory agent or for use in the prevention, amelioration or treatment of any disease or condition as described above, e.g., an autoimmune of inflammatory disease or condition.